First of all, it is important to understand why they are positioning Oracle Real Applications Clusters. Frequently the customers have needs like availability or scalability in their infrastructure, Oracle RAC solution delivers 24/7 database availability, performance, and scalability.
I'm curious though ... exactly what sorts of fears are you hearing in your company, if it a price issue you can start without it but to be honest you will be loosing:

If you or your team are in doubt about licenses you can start using non perpetual license, I understand you can license oracle products from 1 to 5 years so if something goes wrong you can come back and use a simple oracle instance without cluster.

in our company we run 4 separate database servers, we want to change this servers for 1 RAC solution, the problem is that we can't make a consolidation of this three servers ( We need it in production asap and making this will take a while ),